// Released under the MIT/X11 license
// http://www.opensource.org/licenses/mit-license.php
"use strict";
// ============================================================================
// Color management methods
// originally from
// http://www.mjijackson.com/2008/02\
// /rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript
var Color = exports.Color = function Color(r, g, b) {
this.Luminosity = 0.85;
this.Desaturated = 0.4;
if (r instanceof Array) {
this.r = r[0];
this.g = r[1];
this.b = r[2];
} else {
this.r = r;
this.g = g;
this.b = b;
}
};
Color.prototype.update = function(r, g, b) {
this.r = r;
this.g = g;
this.b = b;
};
Color.prototype.hs = function(nStr) {
if (Number(nStr) === 0) {
return "00";
} else if (nStr.length < 2) {
return "0" + nStr;
} else {
return nStr;
}
};
Color.prototype.toString = function() {
var rH = Number(this.r.toFixed()).toString(16);
var gH = Number(this.g.toFixed()).toString(16);
var bH = Number(this.b.toFixed()).toString(16);
return "#" + this.hs(rH) + this.hs(gH) + this.hs(bH);
};
/**
* Converts an RGB color value to HSL. Conversion formula adapted from
* http://en.wikipedia.org/wiki/HSL_color_space. Assumes r, g, and b are
* contained in the set [0, 255] and returns h, s, and l in the set [0, 1].4343
*
* @param Number r The red color value
* @param Number g The green color value
* @param Number b The blue color value
* @return Array The HSL representation
*/
Color.prototype.hsl = function() {
var r = this.r / 255;
var g = this.g / 255;
var b = this.b / 255;
var max = Math.max(r, g, b), min = Math.min(r, g, b);
var h, s, l = (max + min) / 2;
if (max === min) {
h = s = 0; // achromatic
} else {
var d = max - min;
s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
switch (max) {
case r:
h = (g - b) / d + (g < b ? 6 : 0);
break;
case g:
h = (b - r) / d + 2;
break;
case b:
h = (r - g) / d + 4;
break;
}
h /= 6;
}
return [ h, s, l ];
};
/**
* Converts an HSL color value to RGB. Conversion formula adapted from
* http://en.wikipedia.org/wiki/HSL_color_space. Assumes h, s, and l are
* contained in the set [0, 1] and returns r, g, and b in the set [0, 255].
*
* @param Number h The hue
* @param Number s The saturation
* @param Number l The lightness
* @return Array The RGB representation
*/
Color.prototype.hslToRgb = function(h, s, l) {
function hue2rgb(p, q, t) {
if (t < 0) {
t += 1;
}
if (t > 1) {
t -= 1;
}
if (t < 1 / 6) {
return p + (q - p) * 6 * t;
}
if (t < 1 / 2) {
return q;
}
if (t < 2 / 3) {
return p + (q - p) * (2 / 3 - t) * 6;
}
return p;
}
var r, g, b;
if (s === 0) {
r = g = b = l; // achromatic
} else {
var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
var p = 2 * l - q;
r = hue2rgb(p, q, h + 1 / 3);
g = hue2rgb(p, q, h);
b = hue2rgb(p, q, h - 1 / 3);
}
return [ r * 255, g * 255, b * 255 ];
};
/**
* Converts an RGB color value to HSV. Conversion formula adapted from
* http://en.wikipedia.org/wiki/HSV_color_space. Assumes r, g, and b are
* contained in the set [0, 255] and returns h, s, and v in the set [0, 1].
*
* @param Number r The red color value
* @param Number g The green color value
* @param Number b The blue color value
* @return Array The HSV representation
*/
Color.prototype.hsv = function() {
var r = this.r / 255;
var g = this.g / 255;
var b = this.b / 255;
var max = Math.max(r, g, b), min = Math.min(r, g, b);
var h, s, v = max;
var d = max - min;
s = max === 0 ? 0 : d / max;
if (max === min) {
h = 0; // achromatic
} else {
switch (max) {
case r:
h = (g - b) / d + (g < b ? 6 : 0);
break;
case g:
h = (b - r) / d + 2;
break;
case b:
h = (r - g) / d + 4;
break;
}
h /= 6;
}
return [ h, s, v ];
};
/**
* Converts an HSV color value to RGB. Conversion formula adapted from
* http://en.wikipedia.org/wiki/HSV_color_space. Assumes h, s, and v are
* contained in the set [0, 1] and returns r, g, and b in the set [0, 255].
*
* @param Number h The hue
* @param Number s The saturation
* @param Number v The value
* @return Array The RGB representation
*/
Color.prototype.hsvToRgb = function(h, s, v) {
var r, g, b;
var i = Math.floor(h * 6);
var f = h * 6 - i;
var p = v * (1 - s);
var q = v * (1 - f * s);
var t = v * (1 - (1 - f) * s);
switch (i % 6) {
case 0:
r = v;
g = t;
b = p;
break;
case 1:
r = q;
g = v;
b = p;
break;
case 2:
r = p;
g = v;
b = t;
break;
case 3:
r = p;
g = q;
b = v;
break;
case 4:
r = t;
g = p;
b = v;
break;
case 5:
r = v;
g = p;
b = q;
break;
}
return [ r * 255, g * 255, b * 255 ];
};
/**
* Provide
*/
Color.prototype.lightColor = function() {
var hslArray = this.hsl();
var h = Number(hslArray[0]);
var s = Number(hslArray[1]) * this.Desaturated;
var l = this.Luminosity;
var desA = this.hslToRgb(h, s, l);
return new Color(desA[0], desA[1], desA[2]);
};
